PHILADELPHIA — After several forgettable efforts in a row at La Salle, the University of Massachusetts finally delivered a memorable win at Tom Gola Arena.

Chaz Williams’ driving layup with 8.1 seconds left gave the Minutemen a one-point lead and Raphiael Putney’s block of Jerrell Wright’s shot at the buzzer sealed a 61-60 win over the Explorers, Wednesday.

La Salle led 58-57 with just over a minute left, when Terrell Vinson missed a shot in traffic for UMass. Cady Lalanne got the rebound, but he missed too. La Salle appeared to have the rebound, but Vinson tied up Sam Mills to force the alternating possession, keeping the ball for UMass.

Out of a timeout, Vinson spun in traffic and banked the ball in to put the Minutemen up 59-58 with 51 seconds left.

The Explorers attacked quickly and Tyreek Duren hit a layup driving to the basket putting the home team ahead 60-59 with 38 seconds left.

Williams took his time coming up the floor. With the defense playing off him, he hung back, talking to UMass coach Derek Kellogg and guard Freddie Riley, wiping his hands on his shoes and directing traffic. With 10 seconds left, Williams took off, using a Lalanne screen to drive hard to the basket for an easy layup.

“I really just wanted to make a play,” Williams said. “I wasn’t making shots all day so I was really looking to pass. But (Ramon) Galloway was hugging Putney, and that allowed me to get to the rim, not to mention the great screen by Cady.”

After holding Williams to four points, six assists and six rebounds, La Salle coach John Giannini was disappointed in the late breakdown.

“You couldn’t possibly cover a simple ball screen worse than we did on that play,” Giannini said. “They set a screen for him and he went to the basket for a layup and nobody tried to stop him.”

The Explorers hurried the ball up the floor. Duren got deep in the paint but fumbled the ball. It pinballed to Wright on the left baseline. He rushed a shot, but Putney got his finger tips on it as the clock ran out.

“That was a very relieving feeling,” Putney said smiling.

The UMass bench spilled onto the floor in celebration.

“That was a great basketball game against a team we have the utmost respect for,” Kellogg said. “Our guys came in and competed at a high level and really this is what Atlantic 10 basketball is all about, two pretty good teams going at it coming down to the last possession on both ends of the floor. We were fortunate to win.”

The Minutemen, who fell behind by 26 last year at La Salle, avoided the early hole this time and led 33-27 at intermission on the strength of 11 first-half points by Putney, who finished with 17.

UMass, at least temporarily, also expelled its early second-half demons pushing its lead to 45-36 with 14:31 left when Vinson hit the second of two free throws.

Riley then gambled, lunging for a steal and a would-be breakaway, but he was a half-second late and his momentum carried him over half court and out of position. La Salle turned the man advantage into an open 3-pointer for Galloway that made it 45-39.

At the other end, after La Salle batted a pass out of bounds, UMass had to call timeout when Sampson Carter couldn’t inbound the ball.

Out of the break, Carter struggled to find an open teammate again. He tried to loft a pass to Putney, but Galloway stole it for an easy dunk to cut UMass’ lead to 45-41 with 13:03 left.

After a Putney miss, Galloway (16 points) hit another 3 to make it 45-44 with 12:30 left.

From there the two teams went back and forth exchanging the lead six times before the final horn.

“We lost to a very good team,” said Giannini, whose squad upset two ranked teams last week. “I knew it was a very good team. ... I’m phenomenally disappointed, but not surprised. I kind of saw this coming.”

PHILADELPHIA — After four straight losses to La Salle at Tom Gola Arena and seven losses in its last eight games against the Explorers, University of Massachusetts coach Derek Kellogg had a feeling Wednesday’s game would be different. “The guys had a different edge about them. They were very focused, paid attention to details,” Kellogg said after his team’s 61-60 …